It depends. I'm technically a writer for 46 pubs and have written for about a dozen, most of which I like. Whether I submit to a pub depends on 1) whether a story might benefit from the extra boost of a pub's audience and 2) whether I know of a good pub for the topic. For example, @Fanfare is a great place to write about TV, movies, gaming, and a few other topics (good writers, v. engaged audience, great editor in @EricPierce, etc.), so I'd send anything on those subjects there. Are you looking for a publication with a specific slant?